Imagine a world where alcoholism can be assessed and monitored in the same way that we diagnose and monitor diabetes with a Hemoglobin A1c (HbA1c). In a recent Phase II project (whose subject collection has closed), Behavioral Diagnostics has taken the first step to that better world by developing a droplet digital PCR (ddPCR) panel that is capable of identifying heavy alcohol consumption with an Receiver Operator Characteristic (ROC) area under the curve (AUC) of >0.98. This panel, which uses the DNA from only one drop of blood, is already in initial commercial introduction. In completion to a pledge that we made when we accepted funding for the above project, we now propose to identify and develop a ddPCR marker panel for sensitively and specifically assessing alcohol abstinence. When completed, this tool could have substantial impact on clinical treatment. Specifically, an index of these ddPCR markers could be used to precisely monitor patients undergoing outpatient alcohol therapy for compliance with treatment-potentially freeing up more intensive, often inpatient treatment resources for those patients who are failing outpatient treatment. To accomplish this task, we propose to extend our prior 2014 studies of abstinence induced methylation changes with an additional genome wide methylation assessment of DNA from 70 heavily drinking subjects as they enter (T1) and exit (T2) from 30 day residential therapy. We will meta-analyze those data to identify the CpG loci whose change in methylation is most highly associated with alcohol abstinence. We will then construct ddPCR methylation assays for a subset of these loci, validate assay performance using the Illumina array data, and then test their performance in an independent test set of 40 subjects with both T1 and T2 data. This project is highly feasible because all of the biomaterial and data have been collected. The team is well prepared and has a published track record with this type of approach. Dr. Philibert is the CEO of Behavioral Diagnostics and an internationally known expert in both epigenetics and ddPCR. He is assisted by Dr. Meesha Dogan, an expert in big data analyses, Dr. Jeff Long, a well-known biostatistician, a bioethicist, Dr. Cheryl Erwin and Dr. John Mendelson, a well-known addiction specialist. It is innovative because these NextGen approaches have not yet been clinically implemented but yet are desperately needed. Finally, the environment is excellent. Behavioral Diagnostics is established company with protective IP. As a direct result, we will develop an assay for loci whose change in methylation status is most predictive of alcohol cessation. In Phase II, we will further translate this into a highly sensitive tool for guiding clinical treatment and improving treatment of alcohol cessation.